Effects of Fas in combined treatment of TRAIL and arsenic trioxide-induced apoptosis in human gastric cancer cells

OBJECTIVE:To study the effects of Fas in combined treatment of TRAIL(tumor necrosis factor-related apoptosis-inducing ligand) and arsenic trioxide(As2O3)-induced apoptosis in human gastric cancer SGC-7901 cells. METHODS:SGC-7901 cells were cultured in vitro, Sense and Antisense SGC-7901 cells were obtained from transfection of sense and antisense oligo nucleic acid, respectively. Untransfected, Sense and Antisense cells were treated with 0.5 μg/ml As2O3+0.2 μg/ml TRAIL, respectively. Cell proliferation was evaluated by MTT assay after 24, 48 and 72 h; cell colony morphologies were examined under inverted microscope after 48 h; apoptosis rate measured by DAPI staining and flow cytometer; and Fas, FADD and Parp expression determined by Western blot. RESULTS:Treatment by Fas antisense oligo nucleic acid transfection decreased the number of dead cells as detected by microscopy, exerted cell growth inhibition and As2O3+TRAIL-induced apoptosis effects. The expressions of Fas,FADD and activated Parp were all down-regulated (P0.05). CONCLUSION:Fas signaling pathway may be important in the process of SGC-7901 apoptosis induced by combined treatment of As2O3 and TRAIL.